My choice:
1) Tiranium Internet Security free.
2) Qihoo 360 Total Security free.
3) Eset Nod32 Antivirus (surcharge).
4) Kaspersky Internet Security (surcharge).
1) Kaspersky (very good suite)
2) ESET (fast response detection)
3) Norton (light and strong cloud reputation feature)
4) Avast ( tons of shields that protects almost all areas, and now with Hardened mode for total block applications)
5) Qihoo 360 ( multi engines + in house components + cloud)